For my second mushroom dyeing project, I again decided to use the Boletus edulis that had popped up under the oak tree in our yard after fall and winter rains, and to recycle another cotton dish towel in my stash. The dish towel had been mordanted with alum, and I planned to use titanium oxalate as a mordant additive for this dye experiment.
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| A colony of Boletus edulis under the oak tree |
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| Greenish-yellow mushroom underside (click on the picture to see the pores) |
The dye color for B. edulis comes from the mushroom cap underside, which is very spongy. I separated the spongy underside to harvest the dye material. The color is greenish-yellow.
Extract the Dye
For this project, I had previously extracted the dye, and divided it for three different projects (with the plan to use alum, titanium oxalate, and ferrous sulfate as three separate mordant additives). For information about extracting the dye, see Dye Project: Bolete with Alum, the "Extract the Dye" section. Note that by this time, a film of mold had started to grow on the surface of the dye liquid, but I just skimmed it off. The pH of the liquid still registered 3 (moderately acid).
Dye the Fabric
Dye the fabric with the mushroom dye liquid. For this experiment, I recycled a cotton dish towel that had been mordanted with alum and then solar-dyed with Pittosporum capsules, which had produced a pale yellow (see Dye Project: Pittosporum). I used a third of the dye and added titanium oxalate as a mordant additive, saving the rest of the dye extract for one more future experiment.
Titanium produces a distinct palette (for example it gives a bright orange when combined with tannin). Some Boletus spp., including Boletus edulis, contain tannins among their bioactive compounds. More on titanium oxalate.
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| Boletus dye pot with titanium oxalate additive |
Place the extracted mushroom dye in a dye pot and stir in 1/2 tsp titanium oxalate (.49 ounce) as an additive (7-10% WOF). I tested the pH of the liquid, which now registered 2 (strongly acid). Meanwhile, place the dish towel in clear water to soak for 20-30 minutes, to enable the fibers to soak up the dye.
Heat the mushroom dye to 185 °F (this takes about an hour to reach the temperature). Squeeze out the wet towel, and place it in the dye. Simmer for one hour, maintaining the temperature at 185°. Add water periodically to keep the fabric covered with dye extract.
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| Steep the cotton fabric overnight |
Turn off the heat and let the fabric steep in the dye overnight. The next day, squeeze out excess dye, rinse the fabric, and then run it through the washing machine (cold water only), and hang to dry.
Full disclosure: I wasn't thinking, and actually added a mild textile soap [like Synthropol or Professional Textile Detergent (a.k.a., Dharma Dyer's Detergent)] to the rinse, and then dried the towel in the dryer (I usually just rinse and hang to dry, and then wash in mild detergent two weeks later, giving the dye time to set). It seemed to work OK, but was not my usual process.
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| Squeeze out excess dye and rinse thoroughly |
The resulting color was an orangey-brown when wet, but it dried to a lighter shade. The photo really doesn't capture the actual color. Once again I wondered if the mushroom dye actually dyed the fabric at all, or did it simply cause a slight over-dye reaction with the previous Pittosporum capsule dye? It will be interesting to see the outcome of the future experiment planned, using iron.
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| The resulting color is a pale orangey-brown |
